The quest to understand who we are and where we come from has long depended on family lore. But when few relatives or traces of history are available, the search can leave the seekers feeling lost. Now, consumer genetics companies are stepping in where families can not. Popularized by US and British television shows featuring celebrities who discover their hidden past, low-cost DNA test kits are offering to help the masses define, or redefine, their identity.

With the click of a mouse and $100, customers will be sent a test tube to spit into and mail back to the company. The saliva is used to sequence a person’s genes and reveal where on Earth they came from.

Countless videos of dramatic ancestry revelations are streaming on YouTube and Facebook, with DNA testers processing the emotions of discovering they are not who they thought they were. For some, it brings relief and a greater sense of self, while others feel let down either by the science or the story they were sold.

Today at 19:30 GMT, in the first of a two-part conversation, The Stream explores the popular quest to define one’s ancestry through online DNA testing.

On today's show, we speak to: 

Julie Granka @juliegranka
Population geneticist, Ancestry DNA

Kevin Jones Giddins
Ancestry DNA user

Joseph Graves @gravesjl55
Evolutionary biologist, North Carolina A&T State University

What do you think? Leave your views in the comment section below.